The statements in this section merely provide background information related to the present disclosure and may or may not constitute prior art.
Transmissions and other powertrain components in automotive vehicles are complex mechanisms controlled by hydraulic systems and electronic control modules. In order to provide proper control, it is necessary to have feedback on the operating conditions and performance of the transmission as the transmission operates. For example, transmissions typically include a plurality of sensors that communicate information indicative of the operating state of the transmission to the electronic controller. These sensors take many forms and perform various functions. For example, it is often desirable to determine the torque on a rotating shaft (rotator) relative to a stationary component (stator). Accordingly, a torque sensor is used to measure the torque. Common torque sensors include strain gages, magnetic or optical sensors, and surface acoustic wave (SAW) sensors. These torque sensors each measure various parameters such as local strain, angular displacement, or strained-induced change on an acoustic wave. Typically these torque sensors have two components including what can generally be referred to as a transmitter and a receiver. The receiver is typically coupled to the stator and the transmitter is coupled to the rotator. In the case of magnetic sensors and SAW sensors, a current is induced through the receiver and torque applied on the rotator is transmitted back to the receiver in a form of current, radio signal or magnetic field which is then converted into an estimated torque.
However, transmission designs are becoming more compact in order to improve cost, mass, fuel economy, etc. To operate properly, the transmission usually requires supply of pressurized oil to lubricate, cool, or operate systems. One issue related to the above described torque sensors is the ability to package and assemble the torque sensor in current and future transmissions that have compact designs while not impeding pressurized oil flow or other necessary operations of the transmission.
While current transmission sensors are useful for their intended purpose, there is room in the art for an improved sensor system for a powertrain component that allows the torque sensor to be packaged in difficult areas of a transmission.